fix(windows): focus donut for context-menu keyboard input (#730)

src/Filee.App/Controls/DonutMenu.cs

@@ -143,6 +143,11 @@ public DonutMenu()
         FlowDirection = FlowDirection.LeftToRight;
         ClipToBounds = false;
         Cursor = new Cursor(StandardCursorType.Hand);
+        // The live click-mode donut handles Tab, arrows, Enter and Escape itself. It must be the focused control
+        // after a context-menu/shortcut launch; otherwise Avalonia has no focused target to which the key events can
+        // be routed. It is focused explicitly by RadialController, so it must not participate in normal Tab order.
+        Focusable = true;
+        IsTabStop = false;
     }
 
     public IReadOnlyList<DonutItem>? Items { get => GetValue(ItemsProperty); set => SetValue(ItemsProperty, value); }

src/Filee.App/Services/RadialController.cs

@@ -610,7 +610,13 @@ private void PlaceAndShow(RadialWindow window, int x, int y, bool activate)
         }
         _visible = true;
         if (activate)
+        {
             window.Activate();
+            // ShowActivated is false because the same window is also used during an OS drag, where taking focus would
+            // break Explorer's drag. Click mode is different: the donut owns the keyboard until it closes, so focus it
+            // explicitly for Tab/arrow/Enter handling.
+            window.DonutControl.Focus();
+        }
     }
 
     private static bool SameFiles(IReadOnlyList<string> a, IReadOnlyList<string> b) =>

tests/Filee.App.Tests/RadialControllerTests.cs

@@ -2,7 +2,9 @@
 // the gesture ends without files, even after a conversion left the ring behind (issue: desktop icons stopped reacting
 // to clicks until Filee quit).
 
+using Avalonia.Headless;
 using Avalonia.Headless.XUnit;
+using Avalonia.Input;
 using Filee.App.Controls;
 using Filee.App.Services;
 using Filee.Core.Presets;
@@ -59,6 +61,26 @@ public void Esc_closes_a_donut_whose_ring_already_finished()
         Assert.False(radial.Window.IsVisible);
     }
 
+    [AvaloniaFact]
+    public void Click_mode_focuses_the_donut_for_tab_flip()
+    {
+        TestServices.EnsureInitialized("en");
+        var radial = AppHost.Get<RadialController>();
+        try
+        {
+            radial.ShowForFiles(400, 400, [@"C:\photos\a.jpg"]);
+            var window = radial.Window!;
+
+            Assert.True(window.DonutControl.IsFocused);
+            window.KeyPress(Key.Tab, RawInputModifiers.None, PhysicalKey.Tab, null);
+            Assert.True(AppHost.Get<Filee.App.ViewModels.RadialViewModel>().IsBackFace);
+        }
+        finally
+        {
+            radial.Close(animate: false);
+        }
+    }
+
     [Fact]
     public void Folders_only_go_into_one_archive()
     {